Methods of raising sunken or stranded vessels



July 25, 1967 3,332,385

METHODS OF RAISING SUNKEN OR STRANDFI') vrassms K. K. Kv KRYER 3 Sheets-Sheet 1 Filed Nov.

K INVENTOR K041, W W

ATTORNEY July 25, 1967 K. K. KRYER 3,332,385

METHODS OF RAISING SUNKEN 'OR STRANDED VESSELS Filed Nov. 1, 1965 3 Sheets-Sheet 2 I INVENTQR KM aw m, u

BY wallow cm, Mam, new

ATTORNEYS United States Patent 3,332,385 METHODS OF RAISING SUNKEN 0R STRANDED VESSELS Karl Kristian Kobs, Kroyer, Vestre Kongevei 80, Viby 1., Denmark Filed Nov. 1, 1965, Ser. No. 505,784 Claims priority, application Denmark, Nov. 4, 1964, 5,429/ 64 14 Claims. (Cl. 11450) ABSTRACT OF THE DISCLQSURE Buoyant plastic bodies in a water container are moved below the surface of the water and released at a place such that they are sucked through the inlet of a Water pump connected to said water container, and carried into a sunken or stranded vessel by a stream of water generated by said pump to raise said vessel.

This invention relates to a method of raising sunken or stranded vessels by introducing into the interior of said vessels buoyant bodies by means of a stream of water.

A serious problem encountered in carrying out a method of the said type consists in creating a stream of water containing said buoyant bodies and introducing said stream of water into said vessel.

It is well-known to introduce big plastic balls having a diameter of, for instance cm. into the hull of a sunken ship through a tube having a slightly greater diameter than that of the plastic balls, by directing a number of downwardly inclined water jets from spaced nozzles mounted in the wall of said tube against the surface of the plastic balls introduced into the tube on board the salvage ship.

However, this method can be used only if the buoyant plastic balls have a uniform size corresponding to the inner diameter of said tube. If balls having a significantly smaller diameter are introduced into said tube together with said big balls the small balls may avoid the water jets from said nozzles and move towards the surface of the Water. Thereby the small balls become wedged between the surfaces of said big balls and the inner wall of said tube thus clogging the tube.

Furthermore, since each nozzle is connected to a pump on board the salvage ship by means of separate pressure water tubes, the prior art apparatus becomes very difficult to handle, especially in rough sea.

It is also well known to introduce pieces of cork into the interior of a sunken ship by passing a stream of water through the lower part of a container filled with said pieces of cork and mounted on the suction side of a centrifugal pump. However, due to the fact that said container will have to be closed during the introduction of buoyant bodies into the stream of water, a continuous flow of buoyant bodies into the hull of said sunken ship cannot be obtained. Furthermore, said apparatus does not permit the ratio between buoyant bodies and water to be varied within wide limits, which may be necessary in order to obtain a proper control of the ship when it is no longer in contact with the sea bed.

The object of the invention is to eliminate the abovementioned drawbacks of the prior art methods and to provide a new, simple and reliable method for introducing continuously into the interior of a sunken or stranded vessel buoyant bodies having varying sizes.

With said object in view there is provided, according to the invention, a method characterized by the steps of introducing buoyant bodies into a water container having a surface which is kept essentially constant, conveying 3,332,385 Patented July 25, 1967 buoyant bodies down below said water surface and releasing said bodies at a place such that during their movement towards said water surface said buoyant bodies will pass so close to the inlet end of the suction pipe of a pump connected to said container to generate said stream of water, that at least some of said buoyant bodies are caught by said stream of water and carried into the interior of said vessel.

By selecting a suitable conveyor for conveying the buoyant bodies down below the water surface, a continuous dosing of buoyant bodies to the stream of water may be obtained. Furthermore, the method according to the invention makes it possible to vary within wide limits the ratio between buoyant bodies and water in said stream of water by varying the speed of said conveyor.

Thus, it has been found possible to obtain a stream of water containing more than 25% by volume of said buoyant bodies without risking any clogging of the tube communicating with the interior of said sunken or stranded vessel and without damaging said buoyant bodies.

The conveyor used for conveying buoyant bodies down below the surface of the water may be in the form of a bucket wheel having perforated buckets. Such a bucket wheel is particularly suitable for varying the dosing of buoyant bodies to said stream of water. Thus, the speed of rotation of said bucket wheel may be varied. Also the position of the perforated buckets in relation to the circumferential direction of the bucket wheel may be changed so as to catch a higher or smaller amount of buoyant bodies floating on the surface of the water. Finally, it is possible to vary the amount of buoyant bodies introduced into said stream of water by creating such currents in the water in said container that a higher or smaller amount of buoyant bodies is carried into the zone adjacent the inlet end of the suction pipe of said pump. Such currents may be created by using a bucket wheel having adjustable propeller-like spokes.

Thus, the use of a bucket wheel enables the salvage captain to change the rate of supply of buoyant bodies to various parts of the interior of the sunken or stranded ship quickly so as to avoid that the vessel capsizes and sinks again when it has been raised from the sea bed.

The buoyant bodies may also be conveyed down below the surface of the water by means of a vertical or an inclined screw mounted in a housing, the upper part of which is formed as a hopper for the buoyant bodies. By changing the speed of rotation of said screw the dosing of buoyant bodies to the stream of water may be varied within very wide limits.

In the method according to the invention, buoyant bodies having varying sizes may be used. Thus, since no selection of particular buoyant bodies is to be made said bodies may be prepared on board the salvage ship. Thus, it becomes unnecessary to provide space for storing on board said ship the space consuming buoyant bodies to be introduced into the hull of the sunken or stranded vessel.

Such buoyant bodies are preferably gas containing polystyrene balls having a size of between 5 and 16 mm. Such balls may be prepared, for example, by heating a commercially available granular activated polystyrene material to a temperature of 120 C. for a time of between 5 and 10 minutes. During said heat treatment the granules swell up to form balls containing a large number of cells and having a rough surface. Due to the large number of inner cells in the polystyrene balls, which have a density of from about 0.03-0.04 gram per cubic cm., said balls are elastic.

The buoyant bodies may also consist of pieces of cellular plastic material. I

Since the plastic balls or pieces of cellular material introduced into the interior of the sunken or stranded vessel as buoyant bodies act as an air cushion, a pressure in both vertical and horizontal direction will be created within said vessel. Said pressure will act upon the reinforced as well as upon the non-reinforced parts of the hull. Therefore, when the external pressure on the sides of the hull decreases as the vessel rises towards the sea level, the non-reinforced parts of the hull may burst. Thus, it may be desirable to cause the buoyant bodies to adhere to each other to form a coherent mass creating a force acting vertically only and exercising a buoyancy which is uniformly distributed over the structure of the vessel located above said mass.

Thus, a thin film of an adhesive is applied to the buoyant bodies when said bodies have been introduced into the interior of the sunken or stranded vessel. By applying the adhesive to the buoyant bodies after their introduction into the interior of the vessel a clogging of the tube through which said buoyant bodies are conveyed to the vessel is avoided.

The application of an adhesive to the buoyant bodies causes said bodies to adhere to each other when subjected to a compression resulting from the pressure created by the underlying layers of buoyant bodies in the hull of said vessel.

The adhesive used is preferably an asphalt which has a high affinity to the plastic material used.

If the buoyant bodies consist of a thermoplastic material the adhesion between said buoyant bodies may be created by heating the surface of said buoyant bodies after being introduced into the interior of said vessel. The heating may be effected, for example, by introducing steam into the hull of said vessel.

The invention also relates to an apparatus for carrying out the method according to the invention. This apparatus is characterized by the fact that it comprises a water pump which on the pressure side is connected to one end of a tube, the other end of which can be inserted in the interior of a sunken or stranded vessel, and which on the suction side, is connected to a suction pipe opening into a water container having means for maintaining the water surface at an essentially constant level, means for introducing buoyant bodies into said container and means for conveying buoyant bodies located on or above the surface of water down below said surface, and to release the buoyant bodies at a place such that during their movement towards the surface said buoyant bodies will pass so close to the inlet end of the suction pipe of a pump connected to said container to generate said stream of water, that at least some of said buoyant bodies are caught by said stream of water and carried into the interior of said vessel.

The water pump is preferably a centrifugal pump which may be used even if the buoyant bodies are of a size greater than the clearance between the blade wheel and the housing of said centrifugal pump. Thus, it has been found possible to use a centrifugal pump having a clearance between the blade wheel and the housing of 8 mm. for introducing into the hull of a sunken vessel buoyant bodies in the form of balls having a diameter of 16 mm.

According to one embodiment of the apparatus according to the invention the means for conveying the buoyant bodies down below the surface of the water consists of a bucket wheel having perforated buckets.

Advantageously, said bucket wheel may be provided with propeller-like spokes having an adjustable pitch.

Moreover, the buckets of said bucket wheel may be adjustable, in relation to the circumferential direction, in such a manner that a higher or smaller amount of buoyant bodies floating on the surface of the water may be caught by said buckets.

According to another embodiment of the apparatus according to the invention, the conveying means consist of a vertical or inclined screw surrounded by a housing, the upper part of which is formed as a hopper for the buoyant bodies.

The invention will now be described in further detail with reference to the drawings, in which FIG. 1 shows a side view of part of one embodiment of the apparatus according to the invention,

FIG. 2 shows a transverse sectional view along the line IIII of the apparatus shown in FIGURE 1, and

FIG. 3 shows a vertical sectional view of another embodiment of the apparatus according to the invention.

In the drawings, 1 indicates a centrifugal pump which is driven by a motor 2. The pressure side of said centrifugal pump 1 is'connected to one end of a tube 3, the other end of which may be inserted into the interior of a sunken or stranded vessel (not shown).

The suction side of the centrifugal pump 1 is connected to one end of the tube 4, the other end of which opens into a water container 5 through an Opening 6. The wa ter container 5 is provided with an overflow pipe 7 which is provided with a screen 8 preventing buoyant bodies 9 located on the surface of the water in the container 5 from being carried away with any excessive amounts of water introduced through a supply tube 10. A bucket wheel 11 is rotatably mounted upon a shaft 12, which is supported by bearings 13 mounted on the inner side of said container 5. The bucket wheel 11 consists of a wheel rim 14 carrying six propeller-like spokes 15 having a pitch which is adjustable during the rotation of said bucket wheel 11 by means not shown. Perforated buckets 16, which are adjustable along an axis parallel to the shaft 12 of the bucket wheel 11, are mounted upon the wheel 11.

The bucket wheel 11 is driven by a motor 18 via a chain or belt drive 17, and a gear 19 is inserted between the motor 18 and the drive 17.

The apparatus also comprises means (not shown) for introducing buoyant bodies into the container 5.

In practising the method according to the invention water is supplied to the container 5 through the pipe 10 in an amount such that the liquid in the container is kept at an essentially constant level above the bottom of the container 5. Surplus water is drained off through the overflow pipe 7. When the motor 18 is started the bucket wheel 11 is caused to rotate in the direction indicated in FIGURE 1. During said movement the buckets 16 will catch a part of the buoyant bodies 9 located on the surface of the Water. Then said buoyant bodies are conveyed down into the water in which they are released in a position below the opening 6 and start to rise. The strong stream of water through the opening 6, generated by the pump 1, catches a part of the buoyant bodies released from the buckets 16 and said buoyant bodies are then carried through the centrifugal pump 1 and into the tube 3, from which they are released in the interior of the sunken or stranded vessel. By regulating the speed of rotation of the bucket Wheel 11 by means of the gear 19, the dosing of buoyant bodies to the stream of water through the centrifugal pump may be adjusted. Said dosing may also be regulated by changing the pitch of the propeller-like spokes 15 so that there is generated a stronger or weaker current of water in the container 5 in a direction towards the opening 6. Also the position of the buckets 16 may be changed to vary the amount of buoyant bodies caught by said buckets 16. Thus, there will be several possibilities of regulating the introduction of buoyant bodies into the sunken or stranded vessel without changing the speed of rotation of the centrifugal pump. This may be desirable in order to avoid an over-dosage of buoyant shown). The top of the housing 26 is formed as a hopper 27 serving to hold buoyant bodies 28.

The bottom of the housing 26 opens into a chamber 29 communicating with an inlet opening 30 of a pump 31. The pressure side of said pump 31 is connected to one end of a tube 32, the other end of which can be inserted into the interior of a sunken or stranded vessel. The chamber 29 is connected to the surrounding mass of liquid 33 by means of a tube 34. Mounted above the free end of said tube 34, an inverted hopper 35 is provided, which hopper 35 is connected to a pipe 36 terminating outside the container above the liquid level therein.

The top portion of the container 21 is connected to a tube 37 for introducing buoyant bodies into the container 21. At the upper edge of the hopper 27 a perforated ring tube 38 is mounted for supplying liquid to the inner side of said hopper 27.

The top of the container 21 is formed like a funnel 39 allowing air which is introduced into the container 21 together with the buoyant bodies to escape to the atmosphere.

In operation the pump 31 generates a stream of water in the tube 32 by sucking water through the tube 34 and the chamber 29. The current generated in said chamber 29 will carry buoyant bodies introduced into said chamber by means of the rotating screw 25, into the inlet opening 30 of said pump 31. The buoyant bodies are introduced into the container 21 through the tube 37 in a stream of air. These buoyant bodies descend until they contact the inner side of the hopper 27 or buoyant bodies previously introduced into said hopper 27. In order to bring said buoyant bodies 28 into the working area of the screw conveyor a film of flowing water may be provided on the inner side of the said hopper 27 by supplying water through the ring tube 38. In order to facilitate the movement of buoyant bodies 28 into the working area of the screw 25, the upper portion of said screw is conical.

In case the pump 31 fails to operate, the buoyant bodies introduced into the chamber 29 will not be compressed therein but will be discharged through the pipe 34 and discharged on the outside of the container 21.

I claim:

1. A method of raising sunken or stranded vessels by introducing into the interior of said vessels buoyant bodies by means of a stream of water, characterized by introducing said buoyant bodies into a water container having a surface which is maintained at an essentially constant level, conveying buoy-ant bodies down below said surface of the water and releasing said buoyant bodies at a place such that during their movement towards the surface said buoyant bodies will pass so close to the inlet end of the suction pipe of a pump connected to said container to generate said stream of water, that at least some of said buoyant bodies are caught by said stream of water and carried into the interior of said vessel.

2. A method as in claim 1, characterized in that the dosing of buoyant bodies into the stream of water is regulated by generating a current in the water in said container to carry a higher or smaller amount of buoyant bodies towards the inlet end of said suction pipe.

3. A method as in claim 1, characterized in that the buoyant bodies are conveyed down below the surface of the water by means of a bucket wheel having perforated buckets, and that the dosing of buoyant bodies into the stream of Water is regulated by changing the speed of rotation of said bucket wheel or the position of the perforated buckets in relation to the circumferential direction of the bucket wheel.

4. A method as in claim 1, characterized in that the buoyant bodies are conveyed down below the surface of the water by means of a vertical or an inclined screw mounted in a housing, the upper part of which is formed as a hopper to hold the buoyant bodies.

'5. A method as in claim 1, characterized in that a thin film of an adhesive is applied to said buoyant bodies after their introduction into the interior of said sunken or stranded vessel.

6. A method as in claim 5, characterized in that the adhesive used is asphalt.

7. A method as in claim 1, characterized in that the buoyant bodies are made from a thermoplastic material and are subjected to a heating after their introduction into said vessel to cause said buoyant bodies to adhere to each other.

8. An apparatus for carrying out the method as in claim 1, characterized in that it comprises a Water pump which on the pressure side is connected to one end of a tube, the other end of which can be inserted into the interior of a sunken or stranded vessel, and which on the suction side is connected to a suction pipe opening into a water container having means for maintaining the surf-ace of water at an essentially constant level, means for introducing buoyant bodies into said container, and means for conveying buoyant bodies located on or above the surface of the water down "below said surface, and to release said buoyant bodies at a place such that during their movement towards said water surface said buoyant bodies will pass close to the inlet end of said suction pipe so that at least some of said buoyant bodies are caught by the stream of water generated by said pump.

9. An apparatus as in claim 8, characterized in that the conveying means consist of a bucket wheel having perforated buckets.

10. An apparatus as in claim 9, characterized in that the bucket wheel is provided with propeller-like spokes the pitch of which may be regulated.

11. An apparatus as in claim 9, characterized in that the buckets of said bucket wheel are adjustable in relation to the circumferential direction of said bucket wheel.

12. An apparatus as in claim '8, characterized in that the conveying means comprises a vertical or an inclined screw mounted in a housing, the upper part of which is formed as a hopper to hold the buoyant bodies.

13. An apparatus as in claim 8, characterized in that it also comprises means for supplying an adhesive to a zone in the interior of a vessel to be raised adjacent the outlet end of the tube connected to said pump.

14. An apparatus as in claim 8, characterized in that it comprises mean-s for introducing a 'heating medium into the interior of a vessel to be raised.

References Cited UNITED STATES PATENTS 1,772,709 8/ 1930 Culbertson 114-50 2,844,116 7/1958 Potter 114-50 2,857,873 10/1958 Norelli et a1 1145O MILTON BUCHLER, Primary Examiner.

ANDREW H. FARRELL, Examiner. 

1. A METHOD OF RAISING SUNKEN OR STRANDED VESSELS BY INTRODUCING INTO THE INTERIOR OF SAID VESSELS BUOYANT BODIES BY MEANS OF A STREAM OF WATER, CHARACTERIZED BY INTRODUCING SAID BUOYANT BODIES INTO A WATER CONTAINER HAVING A SURFACE WHICH IS MAINTAINED AT AN ESSENTIALLY CONSTANT LEVEL, CONVEYING BUOYANT BODIES DOWN BELOW SAID SURFACE OF THE WATER AND RELEASING SAID BUOYANT BODIES AT A PLACE SUCH THAT DURING THEIR MOVEMENT TOWARDS THE SURFACE SAID BUOYANT BODIES WILL PASS SO CLOSE TO THE INLET END OF THE SUCTION PIPE OF A PUMP CONNECTED TO SAID CONTAINER TO GENERATE SAID STREAM OF WATER, THAT AT LEAST SOME OF SAID BUOYANT BODIES ARE CAUGHT BY SAID STREAM OF WATER AND CARRIED INTO THE INTERIOR OF SAID VESSEL. 